I don't ever sleep or stay in a house, or anywhere at anythime with out a light on. Even the dimmest light is good enough. I won't look into a room until the light is on....I reach around to the light switch before looking in. I know it is all rediculous but i am too afraid of what i will see....what is there .....what ever. There are no specific things except death of other people that i am afraid of seeing. Which is part of my disorder and i knwo it is rediculous and not real, but can't shake it....ior as my psychologist says, hasn't YET shaken it.